The present invention relates to an improvement of a mobile carriage used, for example, as a pest control apparatus for the growing of vegetables in greenhouses.
The pest control of vegetables growing in greenhouses is generally carried out by using a manual sprayer because of the limited space for working in a small greenhouse. However, since there is a great danger of chemical injury to the human body, a so-called hose-car is sometimes used in which an automatic hose winding reel and a spray nozzle boom are mounted on a mobile carriage which automatically runs along a furrow in a back and forth motion, as disclosed in Japanese Patent Publication No. 59-8187.
Conventional house-cars of either the two-wheel or four-wheel drive types, however, involve certain drawbacks with respect to running along furrows and thus cannot be operated in a completely automatic manner.
Such conventional house-cars also have a disadvantage in that they are incapable of making sharp turns and cannot be easily turned when it is desired to enter into a next furrow.